Method and apparatus for timing advance validation in a wireless communication system

ABSTRACT

A method and device are disclosed from the perspective of a UE (User Equipment). In one embodiment, the method includes the UE receiving a first signaling to configure a preconfigured uplink resource (PUR) to be used in a cell. The method further includes the UE determining whether to use the PUR in the cell at least based on whether a timing advance is valid, wherein whether the timing advance is valid is based on a difference between a first measurement result and a second measurement result, and wherein the first measurement result is not a cell measurement quantity of the cell.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present Application claims the benefit of U.S. Provisional PatentApplication Ser. No. 62/912,880 filed on Oct. 9, 2019, the entiredisclosure of which is incorporated herein in their entirety byreference.

FIELD

This disclosure generally relates to wireless communication networks,and more particularly, to a method and apparatus for timing advancevalidation in a wireless communication system.

BACKGROUND

With the rapid rise in demand for communication of large amounts of datato and from mobile communication devices, traditional mobile voicecommunication networks are evolving into networks that communicate withInternet Protocol (IP) data packets. Such IP data packet communicationcan provide users of mobile communication devices with voice over IP,multimedia, multicast and on-demand communication services.

An exemplary network structure is an Evolved Universal Terrestrial RadioAccess Network (E-UTRAN). The E-UTRAN system can provide high datathroughput in order to realize the above-noted voice over IP andmultimedia services. A new radio technology for the next generation(e.g., 5G) is currently being discussed by the 3GPP standardsorganization. Accordingly, changes to the current body of 3GPP standardare currently being submitted and considered to evolve and finalize the3GPP standard.

SUMMARY

A method and device are disclosed from the perspective of a UE (UserEquipment). In one embodiment, the method includes the UE receiving afirst signaling to configure a preconfigured uplink resource (PUR) to beused in a cell. The method further includes the UE determining whetherto use the PUR in the cell at least based on whether a timing advance isvalid, wherein whether the timing advance is valid is based on adifference between a first measurement result and a second measurementresult, and wherein the first measurement result is not a cellmeasurement quantity of the cell.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a diagram of a wireless communication system according toone exemplary embodiment.

FIG. 2 is a block diagram of a transmitter system (also known as accessnetwork) and a receiver system (also known as user equipment or UE)according to one exemplary embodiment.

FIG. 3 is a functional block diagram of a communication system accordingto one exemplary embodiment.

FIG. 4 is a functional block diagram of the program code of FIG. 3according to one exemplary embodiment.

FIG. 5 shows an example of Timing Advance (TA) validation forPreconfigured Uplink Resource (PUR) according to one exemplaryembodiment.

FIG. 6 shows an example of UE movement in a multi-beam cell according toone exemplary embodiment.

FIG. 7 shows an example of serving Reference Signal Received Power(RSRP) change derivation according to one exemplary embodiment.

FIG. 8 is diagram according to one exemplary embodiment.

FIG. 9 is a diagram according to one exemplary embodiment.

FIG. 10 is a flow chart according to one exemplary embodiment.

FIG. 11 is a flow chart according to one exemplary embodiment.

DETAILED DESCRIPTION

The exemplary wireless communication systems and devices described belowemploy a wireless communication system, supporting a broadcast service.Wireless communication systems are widely deployed to provide varioustypes of communication such as voice, data, and so on. These systems maybe based on code division multiple access (CDMA), time division multipleaccess (TDMA), orthogonal frequency division multiple access (OFDMA),3GPP LTE (Long Term Evolution) wireless access, 3GPP LTE-A orLTE-Advanced (Long Term Evolution Advanced), 3GPP2 UMB (Ultra MobileBroadband), WiMax, 3GPP NR (New Radio), or some other modulationtechniques.

In particular, the exemplary wireless communication systems devicesdescribed below may be designed to support one or more standards such asthe standard offered by a consortium named “3rd Generation PartnershipProject” referred to herein as 3GPP, including: TS 38.304 V15.5.0, “NR,User Equipment (UE) procedures in Idle mode and RRC Inactive state”;R4-1910176, “LS on signalling measurement thresholds for validating theTA for PUR”; RP-192160, “Summary of email discussion on NR-Light”,Ericsson; R2-1912001, “Report of 3GPP TSG RAN2 #107 meeting, Prague,Czech Republic”; R4-1910701, “RAN4 #92 Meeting report” (available athttps://www.3gpp.org/ftp/tsg_ran/WG4_Radio/TSGR4_92/Report/); 3GPP TSGRAN2 #107 Chairman's Notes; 3GPP TSG RAN1 #96 Chairman's Notes; 3GPP TSGRAN1 #96bis Chairman's Notes; 3GPP TSG RAN1 #97 Chairman's Notes;Wikipedia article entitled “Timing advance” (available athttps://en.wikipedia.org/wiki/Timing_advance); TS 38.300 V15.6.0, “NR,NR and NG-RAN overall description, Stage 2”; TS 38.331 V15.6.0, “NR,Radio Resource Control (RRC) protocol specification”; and TS 38.321V15.6.0, “NR, Medium Access Control (MAC) protocol specification”. Thestandards and documents listed above are hereby expressly incorporatedby reference in their entirety.

FIG. 1 shows a multiple access wireless communication system accordingto one embodiment of the invention. An access network 100 (AN) includesmultiple antenna groups, one including 104 and 106, another including108 and 110, and an additional including 112 and 114. In FIG. 1 , onlytwo antennas are shown for each antenna group, however, more or fewerantennas may be utilized for each antenna group. Access terminal 116(AT) is in communication with antennas 112 and 114, where antennas 112and 114 transmit information to access terminal 116 over forward link120 and receive information from access terminal 116 over reverse link118. Access terminal (AT) 122 is in communication with antennas 106 and108, where antennas 106 and 108 transmit information to access terminal(AT) 122 over forward link 126 and receive information from accessterminal (AT) 122 over reverse link 124. In a FDD system, communicationlinks 118, 120, 124 and 126 may use different frequency forcommunication. For example, forward link 120 may use a differentfrequency then that used by reverse link 118.

Each group of antennas and/or the area in which they are designed tocommunicate is often referred to as a sector of the access network. Inthe embodiment, antenna groups each are designed to communicate toaccess terminals in a sector of the areas covered by access network 100.

In communication over forward links 120 and 126, the transmittingantennas of access network 100 may utilize beamforming in order toimprove the signal-to-noise ratio of forward links for the differentaccess terminals 116 and 122. Also, an access network using beamformingto transmit to access terminals scattered randomly through its coveragecauses less interference to access terminals in neighboring cells thanan access network transmitting through a single antenna to all itsaccess terminals.

An access network (AN) may be a fixed station or base station used forcommunicating with the terminals and may also be referred to as anaccess point, a Node B, a base station, an enhanced base station, anevolved Node B (eNB), a network node, a network, or some otherterminology. An access terminal (AT) may also be called user equipment(UE), a wireless communication device, terminal, access terminal or someother terminology.

FIG. 2 is a simplified block diagram of an embodiment of a transmittersystem 210 (also known as the access network) and a receiver system 250(also known as access terminal (AT) or user equipment (UE)) in a MIMOsystem 200. At the transmitter system 210, traffic data for a number ofdata streams is provided from a data source 212 to a transmit (TX) dataprocessor 214.

In one embodiment, each data stream is transmitted over a respectivetransmit antenna. TX data processor 214 formats, codes, and interleavesthe traffic data for each data stream based on a particular codingscheme selected for that data stream to provide coded data.

The coded data for each data stream may be multiplexed with pilot datausing OFDM techniques. The pilot data is typically a known data patternthat is processed in a known manner and may be used at the receiversystem to estimate the channel response. The multiplexed pilot and codeddata for each data stream is then modulated (i.e., symbol mapped) basedon a particular modulation scheme (e.g., BPSK, QPSK, M-PSK, or M-QAM)selected for that data stream to provide modulation symbols. The datarate, coding, and modulation for each data stream may be determined byinstructions performed by processor 230.

The modulation symbols for all data streams are then provided to a TXMIMO processor 220, which may further process the modulation symbols(e.g., for OFDM). TX MIMO processor 220 then provides N_(T) modulationsymbol streams to N_(T) transmitters (TMTR) 222 a through 222 t. Incertain embodiments, TX MIMO processor 220 applies beamforming weightsto the symbols of the data streams and to the antenna from which thesymbol is being transmitted.

Each transmitter 222 receives and processes a respective symbol streamto provide one or more analog signals, and further conditions (e.g.,amplifies, filters, and upconverts) the analog signals to provide amodulated signal suitable for transmission over the MIMO channel. N_(T)modulated signals from transmitters 222 a through 222 t are thentransmitted from N_(T) antennas 224 a through 224 t, respectively.

At receiver system 250, the transmitted modulated signals are receivedby N_(R) antennas 252 a through 252 r and the received signal from eachantenna 252 is provided to a respective receiver (RCVR) 254 a through254 r. Each receiver 254 conditions (e.g., filters, amplifies, anddownconverts) a respective received signal, digitizes the conditionedsignal to provide samples, and further processes the samples to providea corresponding “received” symbol stream.

An RX data processor 260 then receives and processes the N_(R) receivedsymbol streams from N_(R) receivers 254 based on a particular receiverprocessing technique to provide N_(T)“detected” symbol streams. The RXdata processor 260 then demodulates, deinterleaves, and decodes eachdetected symbol stream to recover the traffic data for the data stream.The processing by RX data processor 260 is complementary to thatperformed by TX MIMO processor 220 and TX data processor 214 attransmitter system 210.

A processor 270 periodically determines which pre-coding matrix to use(discussed below). Processor 270 formulates a reverse link messagecomprising a matrix index portion and a rank value portion.

The reverse link message may comprise various types of informationregarding the communication link and/or the received data stream. Thereverse link message is then processed by a TX data processor 238, whichalso receives traffic data for a number of data streams from a datasource 236, modulated by a modulator 280, conditioned by transmitters254 a through 254 r, and transmitted back to transmitter system 210.

At transmitter system 210, the modulated signals from receiver system250 are received by antennas 224, conditioned by receivers 222,demodulated by a demodulator 240, and processed by a RX data processor242 to extract the reserve link message transmitted by the receiversystem 250. Processor 230 then determines which pre-coding matrix to usefor determining the beamforming weights then processes the extractedmessage.

Turning to FIG. 3 , this figure shows an alternative simplifiedfunctional block diagram of a communication device according to oneembodiment of the invention. As shown in FIG. 3 , the communicationdevice 300 in a wireless communication system can be utilized forrealizing the UEs (or ATs) 116 and 122 in FIG. 1 or the base station (orAN) 100 in FIG. 1 , and the wireless communications system is preferablythe NR system. The communication device 300 may include an input device302, an output device 304, a control circuit 306, a central processingunit (CPU) 308, a memory 310, a program code 312, and a transceiver 314.The control circuit 306 executes the program code 312 in the memory 310through the CPU 308, thereby controlling an operation of thecommunications device 300. The communications device 300 can receivesignals input by a user through the input device 302, such as a keyboardor keypad, and can output images and sounds through the output device304, such as a monitor or speakers. The transceiver 314 is used toreceive and transmit wireless signals, delivering received signals tothe control circuit 306, and outputting signals generated by the controlcircuit 306 wirelessly. The communication device 300 in a wirelesscommunication system can also be utilized for realizing the AN 100 inFIG. 1 .

FIG. 4 is a simplified block diagram of the program code 312 shown inFIG. 3 in accordance with one embodiment of the invention. In thisembodiment, the program code 312 includes an application layer 400, aLayer 3 portion 402, and a Layer 2 portion 404, and is coupled to aLayer 1 portion 406. The Layer 3 portion 402 generally performs radioresource control. The Layer 2 portion 404 generally performs linkcontrol. The Layer 1 portion 406 generally performs physicalconnections.

In NR, measurement quantity for cell reselection is specified in 3GPP TS38.304 as follows:

For cell selection in multi-beam operations, measurement quantity of acell is up to UE implementation.

For cell reselection in multi-beam operations, including inter-RATreselection from E-UTRA to NR, the measurement quantity of this cell isderived amongst the beams corresponding to the same cell based onSS/PBCH block as follows:

-   -   if nrofSS-BlocksToAverage (maxRS-IndexCellQual in E-UTRA) is not        configured in SIB2/SIB4 (SIB24 in E-UTRA); or    -   if absThreshSS-BlocksConsolidation (threshRS-Index in E-UTRA) is        not configured in SIB2/SIB4 (SIB24 in E-UTRA); or    -   if the highest beam measurement quantity value is below or equal        to absThreshSS-BlocksConsolidation (threshRS-Index in E-UTRA):        -   derive a cell measurement quantity as the highest beam            measurement quantity value, where each beam measurement            quantity is described in TS 38.215 [11].    -   else:        -   derive a cell measurement quantity as the linear average of            the power values of up to nrofSS-BlocksToAverage            (maxRS-IndexCellQual in E-UTRA) of highest beam measurement            quantity values above absThreshSS-BlocksConsolidation            (threshRS-Index in E-UTRA).

In 3GPP R4-1910176, TA validation for PUR in LTE is specified asfollows:

RAN4 would like to inform RAN2 that RAN4 has discussed and agreed to useK number of measurement thresholds for validating the TA when UE isconfigured to validate the TA using serving cell measurement changemethod. The measurement is RSRP for cat-M and NRSRP for NB-IoT. Thevalue of K is 1 or 2.If K=1 means UE compares the magnitude of the difference in measurementchange with a single threshold to validate the TA for PUR transmission.If K=2 means UE compares the difference in measurement change with anegative (RSRP_(neg)/NRSRP_(neg)) threshold and also compares thedifference in measurement change with a positive(RSRP_(pos)/NRSRP_(pos)) threshold. The UE validates the TA for PURtransmission based on these comparisons.UE needs to be configured about the number of the measurementthreshold(s) as well as the thresholds for validating the TA for PURtransmission.The range of the measurement threshold(s) are specified as follows:

-   -   between N dB to M dB with TBD resolution when two thresholds        (K=2) are used excluding 0 dB value where N<0, and M>0.    -   between H dB to L dB with TBD resolution when single threshold        (K=1) is used excluding 0 dB value where H>0, and L>0 and L>H.

In addition, a tentative agreement was made in the RAN4 #92 meeting (ascaptured in 3GPP R4-1910701) as follows:

Tentative Agreement:

-   -   Both in serving cell relaxed monitoring mode and in sering cell        non-relaxed monitoring mode, if UE is configured with RSRP        change for TA validation, it shall satisfy the following        conditions        -   The first measurement (RSRP1) shall be performed within            following time range:            T1−N≤T1′≤T1+N;        -   The second measurement (RSRP2) shall be performed within            following time range:            T2−M≤T2′<T2;            -   Where T1′ is the time when RSRP1 becomes available, T1                is the time when TA is obtained, N is TBD, T2′ is the                time when RSRP2 becomes available, T2 is the time when                TA is validated, M TBD.    -   Relaxation on serving cell monitoring is allowed regardless of        TA validation mechanism.

In the RAN2 #107 meeting, PUR (Preconfigured Uplink Resource) wasdiscussed and the following agreement was reached (as captured in the3GPP TSG RAN2 #107 Chairman's Notes) as follows:

Agreements

-   -   Valid TA is a requirement in order to initiate D-PUR        transmission.    -   The UE may use the D-PUR resource to send RRCConnectionRequest        or RRCConnectionResumeRequest to establish or resume RRC        connection.        -   FFS: whether the UE can send part of the data using the            padding in this case    -   FFS: whether the UE can segment and send part of the data using        the D-PUR resource    -   For the CP solution, the uplink data are encapsulated as a NAS        PDU in an uplink RRC message transmitted in CCCH.    -   For the UP solution, the uplink data are transmitted in DTCH.    -   After the uplink D-PUR transmission, the UE monitors PDCCH under        the control of a timer:        -   The timer starts after D-PUR transmission.        -   The timer restarts if a scheduling for D-PUR retransmission            is received.        -   The UE considers that the D-PUR transmission has failed if            the timer expires.        -   The timer is stopped when D-PUR procedure ends/succeeds.    -   The downlink RRC response message, if needed, for the CP        solution may include the following optional information:        -   downlink data encapsulated as a NAS PDU (downlink            application layer response or pending data in MME)        -   redirection information        -   D-PUR (re-)configuration and release        -   FFS extendedWaitTime    -   The downlink RRC response message for the UP solution may        include the following optional information:        -   Resume ID        -   NCC (mandatory)—the downlink RRC response message for the UP            solution is always provided.        -   redirection information        -   D-PUR (re-)configuration and release        -   FFS extendedWaitTime    -   The MAC CE for TA update can be sent along with the RRC        transmission of the downlink RRC response message for the CP        solution and UP solution.        -   FFS for CP solution if MAC CE for TA update can be sent            without a downlink RRC response message.    -   After reception of D-PUR transmission, the eNB can move the UE        to RRC connection by RRCConnectionSetup message or        RRCConnectionResume message.    -   Fallback after D-PUR transmission is not successful is not        specified i.e. it is up to UE implementation to initiate legacy        RA, MO-EDT or wait for next D-PUR occasion.        -   FFS how to handle the skip in case of failure (UL or DL)            [ . . . ]            Agreements:    -   TA validation criterion “Serving cell changes” is implicitly        always enabled, which means that TA is considered invalid when        the UE initiates RA procedure in a different cell than where TA        was last validated.    -   Configuration for TA validation criteria is provided in        dedicated RRC signaling.        -   It should be possible to disable each or all of the optional            TA validation criteria (i.e., TA timer, (N)RSRP change) via            RRC signaling.    -   UE keeps the PUR configuration while TA is considered invalid,        but PUR cannot be used until eNB validates the existing        TA/provides a new TA.    -   Working assumption: Counter for D-PUR occasions, i.e., “n”, is        not introduced and “indefinite” or “one-shot” are the only        possible configurations.    -   Anew TA timer is defined for UEs configured with D-PUR in idle        mode.        -   The (re)starting times for TA timer need to be aligned            between UE and eNB. The details of the mechanism are FFS.        -   TA timer is restarted after TA is updated.        -   The value range for the TA timer is FFS. Value of “infinity”            is possible.            Agreements:    -   D-PUR request can be sent only by BL UE, UE in CE or NB-IoT UE;        and which are capable of D-PUR.    -   D-PUR request can be sent when the UE is in RRC_CONNECTED.    -   D-PUR request includes number of PUR grant occasions requested        with possibility to request infinite. FFS other values.    -   UE can request D-PUR release. FFS how.    -   A new RRC message is introduced for transmission of PUR request        when UE is in RRC_CONNECTED (i.e., not for the cases of sending        PUR request during EDT and during PUR).    -   UE-specific PUR (re)configuration can be provided while UE is in        RRC_CONNECTED.    -   PUR (re)configuration can be included in RRC Connection Release.    -   At least the following information can be included in PUR        (re)configurations:        -   “m” consecutive missed allocations before release, FFS            values;        -   Time Alignment Timer for idle mode;        -   RSRP change threshold for Serving cell            [ . . . ]            Agreements    -   For UP solution, when PUR request is being piggybacked in the        PUR transmission, same RRC message used for PUR transmission is        used to include PUR request.        -   PUR (re)configuration can be provided in DL RRC response            message (message FFS) of the D-PUR procedure.            -   Explicit reject message (NW→UE) in response to PUR                request is not introduced            -   Delta configuration is supported for PUR                reconfiguration.            -   If the UE performs EDT or moves to RRC_CONNECTED and                comes back to RRC_IDLE in the same cell, PUR                configuration remains valid unless specifically released                or reconfigured by network or other triggers.            -   PUR can be released explicitly by RRCConnectionRelease                message and DL RRC response message (FFS message) of the                D-PUR procedure.            -   FFS: RRCEarlyDataComplete            -   FFS: When UE initiates RACH/EDT, whether it has D-PUR                configuration(s) is not explicitly notified to the                network.    -   EDT cannot be initiated solely for the purpose of sending PUR        request in EDT Msg3.    -   UE is not restricted from initiating RRC Connection for the        purpose of sending PUR request (i.e. this agreement has no        impact to legacy RRC Connection Establishment/Resume        procedures).        [ . . . ]        RAN2 Confirm the Intention of the Previous Agreement as Follows:        If RRC response message is not needed, eNB may send L1 ACK to        acknowledge the PUR transmission in UL. The L1 ACK concludes the        PUR procedure and UE moves to Idle.

Some texts related to RAN1 agreements for Preconfigured Uplink Resources(PUR) in LTE are provided in the 3GPP TSG RAN1 #96 Chairman's Notes, the3GPP TSG RAN1 #96bis Chairman's Notes, and the 3GPP TSG RAN1 #97Chairman's Notes. The 3GPP TSG RAN1 #96 Chairman's Notes state:

Additional MTC Enhancements

Agreement

In idle mode, the TA validation configuration can include “PUR TimeAlignment Timer”

-   -   Where the UE considers the TA as invalid if the (current        time−time at last TA update)>the PUR Time Alignment Timer    -   Details on how to specify the “PUR Time Alignment Timer” is up        to RAN2        Agreement        In idle mode, when the UE validates TA, the UE considers the TA        for the previous serving cell as invalid if the serving cell        changes    -   Above applies for the case where the UE is configured to use the        serving cell change attribute        Agreement        For dedicated PUR in idle mode, the Dedicated PUR ACK is at        least sent on MPDCCH    -   RAN2 can decide if a higher layer PUR ACK is also supported        Agreement        For dedicated PUR in idle mode, the PUR search space        configuration shall be included in the PUR configuration.    -   PUR search space is the search space where UE monitors for        MPDCCH    -   FFS: Whether PUR search space is common or UE specific        Agreement        When the TA is validated and found to be invalid and the UE has        data to send, the UE can obtain a valid TA and may send data via        legacy RACH or EDT procedures    -   FFS whether only TA is acquired and then data sent on PUR is        supported    -   FFS other approaches to obtain a valid TA        Agreement        When the UE is configured to use several TA validation criteria,        the TA is valid only when all the configured TA validation        criteria are satisfied.        Agreement        For dedicated PUR, in idle mode, the PUR resource configuration        includes at least the following    -   Time domain resources including periodicity(s)        -   Note: also includes number of repetitions, number of RUs,            starting position    -   Frequency domain resources    -   TBS(s)/MCS(s)    -   Power control parameters    -   Legacy DMRS pattern        Agreement        In idle mode, at least the following PUR configurations and PUR        parameters may be updated after a PUR transmission:    -   Timing advance adjustment    -   UE TX power adjustment    -   FFS: Repetition adjustment for PUSCH        FFS: Whether the above update is done in L1 and/or higher layer        Agreement        In idle mode, the PUR search space configuration includes at        least the following:    -   MPDCCH narrowband location    -   MPDCCH repetitions and aggregation levels    -   MPDCCH starting subframe periodicity (variable G)    -   Starting subframe position (alpha_offset)        Agreement        For dedicated PUR in idle mode, the PUR resource configuration        includes at least the following    -   A PUSCH frequency hopping indication to enable or disable legacy        frequency hopping        Agreement        In idle mode, a UE can be configured such that TA is always        valid within a given cell.    -   FFS: up to RAN2 how to implement e.g. PUR Time Alignment        Timer=infinity

Additional Enhancements for NB-IoT

Agreement

When the UE is configured to use several TA validation criteria, the TAis valid only when all the configured TA validation criteria aresatisfied.

Agreement

For dedicated PUR in idle mode, the PUR search space configuration shallbe included in the PUR configuration.

-   -   PUR search space is the search space where UE monitors for        NPDCCH    -   FFS: Whether PUR search space is common or UE specific        Agreement        In idle mode, the TA validation configuration can include “PUR        Time Alignment Timer”    -   Where the UE considers the TA as invalid if the (current        time−time at last TA update)>the PUR Time Alignment Timer    -   Details on how to specify the “PUR Time Alignment Timer” is up        to RAN2        Agreement        In idle mode, when the UE validates TA, the UE considers the TA        for the previous serving cell as invalid if the serving cell        changes    -   Above applies for the case where the UE is configured to use the        serving cell change attribute        Agreement        For dedicated PUR in idle mode, the dedicated PUR ACK is at        least sent on NPDCCH    -   FFS: Whether to introduce new field in DCI or reuse existing        field    -   RAN2 can decide if a higher layer PUR ACK is also supported        Agreement        When the TA is validated and found to be invalid and the UE has        data to send, the UE can obtain a valid TA and may send data via        legacy RACH or EDT procedures    -   FFS whether only TA is acquired and then data sent on PUR is        supported    -   FFS other approaches to obtain a valid TA        Agreement        In idle mode, at least the following PUR configurations and PUR        parameters may be updated after a PUR transmission:    -   Timing advance adjustment    -   UE TX power adjustment    -   FFS: Repetition adjustment for NPUSCH        FFS: Whether the above update is done in L1 and/or higher layer        Agreement        In idle mode, the PUR search space configuration includes at        least the following:    -   NPDCCH repetitions and aggregation levels    -   NPDCCH starting subframe periodicity (variable G)    -   Starting subframe position (alpha_offset)        Agreement        For dedicated PUR, in idle mode, the PUR resource configuration        includes at least the following    -   Time domain resources including periodicity(s)        -   Note: also includes number of repetitions, number of RUs,            starting position    -   Frequency domain resources    -   TBS(s)/MCS(s)    -   Power control parameters    -   Legacy DMRS pattern

The 3GPP TSG RAN1 #96bis Chairman's Notes state:

Additional MTC Enhancements

Working Assumption #1

In idle mode, updating PUR configurations and/or PUR parameters via L1signalling after a PUR transmission is supported

-   -   FFS: Which PUR configurations and PUR parameters will be        signaled via L1    -   FFS: Definition of PUR configurations and PUR parameters        The working assumption will be automatically confirmed if for        some cases L2/L3 signaling is not needed. If RAN2 decides that        L2/L3 signaling is needed for all cases, the working assumption        will be reverted.        Working Assumption #2        For dedicated PUR    -   During the PUR search space monitoring, the UE monitors for DCI        scrambled with a RNTI assuming that the RNTI is not shared with        any other UE        -   Note: It is up to RAN2 to decide how the RNTI is signaled to            UE or derived    -   FFS if the UE monitors any additional RNTI which may be shared        with other UEs.    -   Note: The same RNTI may be used over non-overlapping time and/or        frequency resources        Send an LS to RAN2 to include two above working assumptions. Ask        whether the first bullet in working assumption #2 is feasible.        If it is concluded that working assumption #2 is feasible, the        working assumption #2 will be automatically confirmed.        Agreement        The UE monitors the MPDCCH for at least a time period after a        PUR transmission    -   FFS: Details of the time period    -   FFS: UE behaviour if nothing is received in the time period    -   FFS: If and how often UE monitors MPDCCH after a PUR allocation        in which it has not transmitted        Agreement        The value(s) of RSRP threshold(s) is UE specific        Agreement        The power control parameters within the PUR configuration, shall        at least include:    -   Target UL power level (P_0) for the PUR transmission        Agreement        For dedicated PUR in idle mode, the PUR configuration is        configured by UE-specific RRC signaling.        Additional Enhancements for NB-IoT        Agreement        In idle mode, a UE can be configured such that TA is always        valid within a given cell.    -   Up to RAN2 how to implement        -   e.g. PUR Time Alignment Timer or NRSRP Threshold=infinity            Agreement            The value(s) of NRSRP threshold(s) is UE specific            Agreement            The UE monitors the NPDCCH for at least a time period after            a PUR transmission.    -   FFS: Details of the time period    -   FFS: UE behaviour if nothing is received in that time period.    -   FFS: If and how often UE monitors NPDCCH after a PUR allocation        in which it has not transmitted        Agreement        Reuse existing field(s) of DCI format NO to convey the dedicated        PUR ACK        Agreement        After data transmission on PUR, upon unsuccessful decoding by        eNB, the UE can expect an UL grant for retransmission on NPDCCH.        Other behaviors are FFS.        Working Assumption #1        In idle mode, updating PUR configurations and/or PUR parameters        via L1 signalling after a PUR transmission is supported    -   FFS: Which PUR configurations and PUR parameters will be        signaled via L1    -   FFS: Definition of PUR configurations and PUR parameters        The working assumption will be automatically confirmed if for        some cases L2/L3 signaling is not needed. If RAN2 decides that        L2/L3 signaling is needed for all cases, the working assumption        will be reverted.        Working Assumption #2 For dedicated PUR    -   During the PUR search space monitoring, the UE monitors for DCI        scrambled with a RNTI assuming that the RNTI is not shared with        any other UE        -   Note: It is up to RAN2 to decide how the RNTI is signaled to            UE or derived    -   FFS if the UE monitors any additional RNTI which may be shared        with other UEs.    -   Note: The same RNTI may be used over non-overlapping time and/or        frequency resources        Send an LS to RAN2 to include two above working assumptions. Ask        whether the first bullet in working assumption #2 is feasible.        If it is concluded that working assumption #2 is feasible, the        working assumption #2 will be automatically confirmed. (LS is        approved in eMTC agenda item—see 6.2.1.2)        Agreement        For dedicated PUR in idle mode, the PUR configuration is        configured by UE-specific RRC signaling.

The 3GPP TSG RAN1 #97 Chairman's Notes state:

Additional MTC Enhancements

Agreement

For a given UE, for dedicated PUR in idle mode and for a given CE mode,the same size DCI, the same PUR M-PDCCH candidates, and the same RNTI isused for all DCI messages for unicast transmissions.

Agreement

For dedicated PUR in idle mode and for HD-FDD UEs, the start of the PURSS Window is [x] subframes after the end PUR transmission

FFS: Value of x, and if x is fixed or signaled

FFS: FD-FDD UEs, TDD UEs

FFS: Support for monitoring of PUR SS Window before PUR transmission

Note: The PUR SS Window is the time period where the UE monitors theMPDCCH for at least a time period after a PUR transmission

Agreement

For dedicated PUR in idle mode,

The maximum mPDDCH repetitions, r_(max)-mPDCCH-PUR, is included in thePUR configuration

Agreement

For dedicated PUR in idle mode, the duration of the PUR SS window isconfigured by eNB How the duration is configured, and the possiblevalues, will be decided by RAN2.

Agreement

For dedicated PUR in idle mode, the CE mode is

Option 1: explicitly configured in the PUR configuration.

Option 2: based on CE mode of last connection

Down select in RAN1 #98

Agreement

Select one of the following in RAN1 #98

-   -   Alt1: In idle mode, the PUR search space PRB pairs is configured        between {2, 2+4, 4}PRBs    -   Alt2: In idle mode, the PUR search space PRB pairs is fixed to        2+4 PRBs        Agreement        For dedicated PUR in idle mode, if a UE skips a PUR        transmission, it is not mandated to monitor the associated PUR        SS window        Additional Enhancements for NB-IoT        Agreement        For dedicated PUR in idle mode and for HD-FDD UEs, the start of        the PUR SS Window is [x] subframes after the end PUR        transmission    -   FFS: Value of x, and if x is fixed or signaled    -   FFS: Support for monitoring of PUR SS Window before PUR        transmission        Note: The PUR SS Window is the time period where the UE monitors        the NPDCCH for at least a time period after a PUR transmission        Agreement        NPDCCH candidates are determined by USS like search space    -   FFS: Other details on the USS like search space        -   Type2-CSS can also be discussed as part of the FFS            Conclusion            CBS PUR is not supported in Rel-16            For Further Discussion    -   Aspects related to notifying eNB of unused PUR resources.    -   Potential enhancements of power control mechanisms for PUR. (The        baseline is the existing NB-IoT open loop power control.)

In 3GPP RP-192160, the preliminary discussion result of NR light in 3GPPRAN working group is captured as follows:

3.1 Summary of Use Cases

Companies highlighted three main use cases for NR Light devices:

-   -   Industrial Wireless Sensors (26 companies out of 34)    -   Video surveillance (22 companies out of 34)    -   Wearables (22 companies out of 34)        It is suggested to focus on these 3 use cases in the potential        Rel-17 study/work item.        Industrial Wireless Sensor Networks: Devices in such network        include e.g. pressure sensors, humidity sensors, thermometers,        motion sensors, accelerometers, etc. As compared to URLLC, this        use case is more relaxed in terms of latency and reliability. On        the other hand, the device cost and power consumption should be        lower than in URLLC and eMBB. Use cases are described e.g. in TS        22.104, TR 22.832 and TS 22.804.        Surveillance camera use case covers video surveillance for smart        city, factories industries etc. As example, TS 22.804 describes        smart city use case and requirements for that. The smart city        vertical covers data collection and processing to more        efficiently monitor and control city resources, and to provide        services to city residents.        Wearables use case includes smart watches, rings, eHealth        related devices and some medical monitoring devices etc. One        characteristic for the use case is that the device is small in        size.        In addition, low end smartphones were mentioned by 6 companies.        It is proposed to discuss this use case later on once Rel-16        email discussion on this topic is concluded. With respect to        other use cases beyond that, it is proposed that those are not        discussed explicitly. However, it should be noted that any        solution and a device type that is introduced should be generic        so that it can be applied in many use cases. By this way, market        fragmentation can be avoided.        Deployment scenarios: Most companies mention indoor and outdoor        deployments and FDD/TDD. Around 8 companies explicitly stated        that both FR1 and FR2 should be included whereas 3 companies        want to prioritizes only FR1. Thus it is suggested that both FR1        and FR2 are included in the scope.        3.2 Summary of Key Requirements        The key requirements are divided in the generic and use case        specific requirements:        Generic Requirements:        Device Cost: As Mentioned by Companies, One Main Motivation of        this Study Item is to Lower the UE device cost and complexity as        compared to high-end eMBB device of Rel-15/Rel-16. This is        especially the case for the for industrial sensors. It is        assumed that the cost is reduced by reducing the supported        bandwidth as well as RX antennas. However, it is understood the        system should be backwards compatible and that Rel-15 NR SS/PBCH        blocks should be reused.        Device size: One requirement is that the standard enables a        device design with smaller size.        Coverage: It is common understanding that coverage of the cell        would be similar to Rel-15/16 deployment except that there is        need to compensate for the coverage loss due to reduced number        of Rx antennas, reduced UE bandwidth, transmit power level, and        other UE complexity reductions.        Use Case Specific Requirements:        Industrial wireless sensors: Some reference use cases and        requirements are described in TR 22.832 and TS 22.104:        Communication service availability is 99.99% and end-to-end        latency less than 100 ms. The bit rate requirement is less than        2 Mbps for all use cases and the device is stationary. The        battery should last at least few years. For safety related        sensors, latency requirement is lower, 5-10 ms (TR 22.804)        Video Survaillance: As described in TS 22.804, economic video        bitrate would be 2-4 Mbps, latency <500 ms, reliability        99.0-99.9%. High end video e.g. for farming would require 7.5-25        Mbps. It is noted that traffic is heavy in UL.        Wearables: Many companies mentioned LTE Cat 4 as a reference for        the bitrate, corresponding to 150 Mbps50 Mbps. However, some        companies considered that also lower bitrates (<20 Mbps) can be        utilized, and even 1 Mbps (Sony). Battery of the device should        last multiple days (up to 1 week).        3.3 Summary of Evolution Areas        Companies highlighted four main evolution areas:    -   1. UE complexity reduction or lower UE power class (31 out of 32        companies),    -   2. UE power saving and battery lifetime enhancement (29 out of        32 companies),    -   3. System aspects (28 out of 32 companies), and    -   4. Support high UE density (6 out of 32 companies).        Thus, it is suggested to focus on these 4 evolution areas in the        potential Rel-17 study/work item.        UE complexity reduction or lower UE power class: the features        mentioned by most companies are    -   Reduce number of UE antennas (26 companies): A majority of        companies suggested 1 or 2 RX antennas and 1 TX antenna    -   UE Bandwidth reduction (27 companies): No company suggests to        have maximum UE bandwidth higher than 20 MHz in FR1. Some        companies further suggested UE bandwidth to be limited to 5 or        10 MHz. For FR2, one company suggested UE bandwidth to be no        higher than 40 MHz.    -   Lower UE power class (13 companies): Proposed power levels range        from 4 to 20 dBm.    -   Half-Duplex-FDD (9 companies)    -   Relaxed UE processing time or capability (8 companies)        UE power saving and battery lifetime enhancement: the features        mentioned by most companies are    -   Reduced PDCCH monitoring (17 companies): The enhancements        mentioned include fewer CORESET and search spaces        configurations, and small numbers of blind decodes and CCE        limits.    -   UE power saving in RRC Idle/Inactive (16 companies): Most        companies did not include specific feature proposals, but a few        companies suggested WUS, RRM relaxation    -   Enhanced DRX for RRC Inactive or Idle (7 companies)    -   Optimization for stationary devices with limited mobility (7        companies)        It is noted that power saving is discussed also in another email        discussion. With respect to NR Light, the focus should be in        less frequent data transmission and power consumption in        IDLE/INACTIVE mode.        System aspects mentioned by most companies:    -   Coverage recovery is needed to compensate the device complexity        reduction, especially reduced amount of RX antennas (mentioned        by 23 companies)    -   SSB should be reused and L1 changes minimized (9 companies)    -   Backward compatibility and coexistence with wideband UE should        be ensured (8 companies)    -   UE relay or sidelink was mentioned (9 companies): However, these        topics are addressed the sidelink enhancements email discussion.        Support High UE Density        6 companies suggested to work on this evolution area. However,        no single feature is mentioned by more than 3 companies. The        exact candidate features can be discussed further.        3.4 Summary of ‘Other Comments’        Here are some issues companies brought up. These can be        discussed further.    -   One company mentions that the features potentially introduced in        this SI/WI should be generic and available to any NR UE.    -   Two companies mention that ‘NR-Light’ may not be a suitable name        and that ‘NR-Lightweigth’ or ‘Enhanced support for        lower-complexity NR UEs’ may be more suitable.    -   Two companies comment that the Rel-17 features Small Data        Enhancements, Power Savings in Connected Mode, and Relaying        should generally be applicable to NR-Light UEs. There is need to        coordinate the study/work item scope and avoid overlap.    -   One company thinks the number of new UE categories/types        introduces for NR-Light should be minized to avoid market        fragmentation.

In general, Internet of Things (IoT) has been a very important area tobe developed in 5G. In 3GPP, study and specifications on features tosupport IoT devices are taking place continuously. For example, NR_Light(namely NR_Lite, NR-IoT, NR-Light) is likely to be introduced, e.g. inNR Release 17. The target of NR_Light is mid-end/high-end IoT devices(e.g. industrial sensors, surveillance cameras). Compared to NR eMBB (orNR URLLC) device, characteristics of NR light devices may include lowerdevice complexity, lower cost, lower data rate and higher latency,longer battery life. More details about NR_Light including use cases,key requirements, and evolution area, has been specified in 3GPPRP-192160 as discussed above.

At least one new NR UE capability may be defined for NR_Light UEs. It isassumed that an NR_Light UE connects to gNB rather than eNB. It is alsoassumed that the NR_Light UE supports at least some of the NRtechniques, which may include, for example, Bandwidth part (BWP)operation, beam operation.

To support NR_Light devices (or NR_Light UEs) in NR, some mechanisms toimprove transmission efficiency and reduce power consumption may beintroduced in NR. For example, NR may introduce a mechanism similar toPreconfigured Uplink Resources (PUR) in LTE MTC or NB-IoT. For example,while the UE is in e.g. RRC_IDLE state or RRC_INACTIVE state, when thereis UL data available for transmission, the UE could transmit the UL datausing PUR instead of initiating a RA procedure. The UE could monitorPhysical Downlink Control Channel (PDCCH) for receiving Network (NW)response (for PUR) after transmitting the UL data using PUR. The NWresponse could be an Acknowledgement (ACK) or Negative Acknowledgement(NACK) indication. The NW response could be a Uplink (UL) grantscheduling retransmission of the UL data. The NW response could be aDownlink (DL) assignment scheduling DL data and the UE receives thecorresponding DL data according to the DL assignment. After receivingthe NW response (for PUR), the UE may stay in RRC_IDLE or RRC_INACTIVEstate. After receiving the NW response (for PUR), the UE may enterRRC_CONNECTED state (e.g. in case the DL data includes RRCSetup orRRCResume message).

Before the UE performs a UL transmission, the UE may determine whetheror not the UL data could be transmitted using PUR, based on someconditions. The UL data may include an RRC message (e.g.RRCSetupRequest, RRCResumeRequest, RRCEarlyDataRequest). The UL data mayinclude data coming from application layer. The UE may not initiate a RAprocedure if the UE determines that the UL data could be transmittedusing PUR. The UE may initiate a RA procedure if the UE determines thatthe UL data could not be transmitted using PUR. The UE may initiate anRRC connection establishment procedure and transmits the RRC message(e.g. RRCSetupRequest) during a RA procedure if the UE determines thatthe UL data could not be transmitted using PUR. The UE may initiate anRRC connection resume procedure and transmits the RRC message (e.g.RRCResumeRequest) during a RA procedure if the UE determines that the ULdata could not be transmitted using PUR. The UE may initiate an RRCconnection establishment procedure and transmits the RRC message (e.g.RRCSetupRequest) using PUR if at least the RRC message could betransmitted using PUR. The UE may initiate an RRC connection resumeprocedure and transmits the RRC message (e.g. RRCResumeRequest) usingPUR if at least the RRC message could be transmitted using PUR.

The conditions may include whether the (potential) data size of the ULdata is not larger than a threshold (and the threshold may be predefinedor configured in the PUR configuration). The conditions may includewhether the service type of the UL data is a specific service type (e.g.data from a configured logical channel). The conditions may includewhether the establishment cause is a specific establishment cause (e.g.mo-Data). The conditions may include whether the Serving Cell (on whichthe UE camps) supports PUR (e.g. indicated in the system information).The conditions may include whether the UE has a PUR configuration. ThePUR configuration may include time or frequency resource information forPUR. The PUR configuration may include beam information for PUR, e.g.which beam(s) of the cell is configured with PUR. The PUR configurationmay include parameters related to Timing Advance (TA) validation forPUR. The PUR configuration may include parameters related to PDCCHmonitoring for PUR. The UE may receive the PUR configuration from the NWwhile the UE is in RRC_CONNECTED state. The UE may receive the PURconfiguration from the NW in the DL data after performing the ULtransmission using PUR.

The conditions may include whether or not TA is valid for PUR. The UEdetermines whether or not TA is valid for PUR according to the PURconfiguration. The UE may consider the TA for PUR to be valid if (atleast) a TA timer (for PUR) is running. The UE may consider the TA forPUR to be valid if (at least) the measured Radio Signal Received Power(RSRP) of the Serving Cell is above (or not below) a threshold (and thethreshold could be predefined or configured in the PUR configuration).The conditions may include whether or not the next occurred PUR occasionis not too far away in time domain (e.g. the UE may determine whether ornot the UL data could be transmitted using PUR if the time duration fromthe determination to the next occurred PUR occasion is smaller (or notlarger) than a threshold, and the threshold may be predefined orconfigured in the PUR configuration). The conditions may include whetheror not the time duration between current available PUR occasion and nextavailable PUR occasion is smaller (or not larger) than a threshold (andthe threshold may be included in the PUR configuration). The UEdetermines the next occurred PUR occasion according to the PURconfiguration. The UE performs transmission using PUR on the PURoccasion.

If the UE determines that the UL data could be transmitted using PURbased on at least one of the above listed conditions, the UE mayconsider that there is available PUR or the PUR is available. If the UEdetermines that the UL data could not be transmitted using PUR based onat least one of the above listed conditions, the UE may consider thatthere is no available PUR or the PUR is not available. If the UEdetermines that at least the RRC message could be transmitted using PURbased on at least one of the above listed conditions, the UE mayconsider that there is available PUR or the PUR is available. WhetherPUR is available may be on per beam basis. For example, PUR may beavailable on one beam but may not be available on another beam.

The PUR could be a dedicated PUR (or called D-PUR). From the UE'sperspective, a “dedicated PUR” may imply that the UL resource is notshared with another UE and the NW could identify which UE is performingthe transmission using this dedicated PUR. The UE may not expect anyconflict or collision with other UEs when performing transmission usingthe dedicated PUR. There may be no Contention Resolution required forthe dedicated PUR transmission.

The PUR may be configured to the UE on per beam basis. For example, theUE may be configured with PUR on one beam of a cell but not on anotherbeam of the cell. The network may indicate to the UE which beam(s) wherethe PUR is configured.

In the RAN2 #107 meeting (as discussed in 3GPP R2-1912001), it wasagreed that valid TA is a requirement in order to initiate D-PURtransmission. And the MAC CE for TA update can be sent along with theRRC transmission of the downlink RRC response message for the CPsolution and UP solution.

In the RAN4 #92 meeting (as discussed in 3GPP R4-1910701), under thediscussion of additional MTC enhancements for LTE, there is possibleagreement that eNB can configure any of K=1 and K=2, i.e. one or twothresholds for validating the TA when configured with serving cellmeasurement change attribute.

According to 3GPP R4-1910176, K=1 means that the UE compares themagnitude of the difference in measurement change with a singlethreshold to validate the TA for PUR transmission. And K=2 means that UEcompares the difference in measurement change with a negative(RSRPneg/NRSRPneg) threshold and also compares the difference inmeasurement change with a positive (RSRPpos/NRSRPpos) threshold. The UEvalidates the TA for PUR transmission based on these comparisons.

Timing advance (TA) may be considered as the value corresponding to thelength of time a signal takes to reach the base station (e.g. eNB, gNB)from a UE. Since UEs at various distances from the base station andradio waves travel at the finite speed of light, the previsearrival-time within a time slot can be used by the base station todetermine the distance to the UE. The time at which the UE is allowedfor transmission within a time slot must be adjusted accordingly toprevent collisions with adjacent users. TA is the variable controllingthe adjustment (as discussed in the Wikipedia article entitled “Timingadvance”).

TA validation for PUR (or D-PUR) could be based on the magnitude of thedifference between the serving cell measurement result at a firstparticular timing (e.g. when TA is obtained, last TA validation) and theserving cell measurement result at a second particular timing (e.g. whenTA is validated). If the measurement result changes too much (comparewith one or two thresholds, depending on the configuration), TA could beconsidered as invalid. The serving cell measurement result could beRSRP. An example is shown in FIG. 5 , which illustrates an example of TAvalidation for PUR. If the difference between RSRP2 and RSRP1 fulfillsthe equation (for K=1 or K=2, depending on the configuration of K), thevalidation of TA could be passed (and the maintained TA could beconsidered as valid). Otherwise (i.e. the difference does not fulfillthe equation), the validation of TA could be considered as failed (andthe maintained TA is considered as invalid).

In NR, beamforming may be used. Different beams may have differentmeasurement results, and serving cell measurement result is derived frombeam measurement results of the serving cell. According to the current3GPP TS 38.304, cell measurement result is in general derived from thelinear average of the power values of up to N highest beam measurementquantity values above a configured threshold (see 3GPP TS 38.304 formore detail). As the UE moves in the cell, the beam(s) suitable for PURtransmission may be changed, and the TA validity may depend on thelocation of the UE and the beam(s) used for PUR transmission. ValidatingTA based on current cell measurement result derivation may not beaccurate or sufficient enough.

An example is shown in FIG. 6 , which shows an example of UE movement ina multi-beam cell. In this example, the UE is in location “a” at thefirst particular timing (e.g. the UE obtains TA or validates TA for afirst time when it is in location “a”), and moves to location “b” at thesecond particular timing (e.g. when validating the TA or validates TAfor a second time). At location “a”, cell measurement result is derivedfrom beam 1 and beam 2. At location “b’, cell measurement result isderived from beam 4. It is assumed that the difference between “cellmeasurement results derived at location “a” and location “b” is not overthe threshold(s).

Another example is shown in FIG. 7 , which shows an example of servingcell RSRP change derivation. In this example, the UE is in location “a”at the first particular timing (e.g. when TA is obtained, when TA isvalidated for a first time), and moves to location “b” at the secondparticular timing (e.g. when TA is validated, when TA is validated for asecond time). At location “a”, cell measurement result is derived fromthe linear average of the power values (e.g. RSRP) of beam measurementquantity values of beam 1 and beam 2. At location “b” cell measurementresult is derived from the power value of beam measurement quantityvalue of beam 4. It is assumed that the difference between cellmeasurement results derived at location “a” and location “b” is not overthe threshold(s).

In one aspect, it may be possible that based on the current serving cellmeasurement result derivation, the change in serving cell RSRP is notover the threshold(s) and thus the UE considers the currently maintainedTA as valid. However, the TA is actually not suitable (or valid) forsome of the beams configured for PUR. Selecting these beams for PURtransmission may result in PUR transmission failure. In the aboveexamples, beam 1 may not be suitable for using the maintained TA for PURtransmission when the UE is in location “b”.

In another aspect, it may be possible that based on the current servingcell measurement result derivation, the change in serving cell RSRP isnot over the threshold(s) and thus the UE considers the currentlymaintained TA as valid. However, the TA is actually not valid for PURtransmission. Performing PUR transmission using the TA may result in PURtransmission failure. In the above examples, the TA obtained at location“a” may not compensate the transmission delay accurately at location b”,and thus the TA is not valid.

To solve the issue, TA validation (for PUR or D-PUR) in NR could bebased on beam measurement result(s) and/or specific measurementresult(s) derived from beam measurement result(s) but not follow themethod of serving cell measurement quantity derivation (such as servingcell RSRP), for example, for measurement report or cell reselection (thelinear average of the power values of up to N highest beam measurementquantity values above a configured threshold, as specified in 3GPP TS38.304 as discussed quoted above). The serving cell may comprise aplurality of beams. More details are described below.

TA validation (for PUR or D-PUR) could be based on the differencebetween two measurement results, e.g. the measurement result at a firstparticular timing (such as when the TA was obtained, last TA validation,and/or at location “a” in the above examples) and the measurement resultat a second particular timing (e.g. when the TA is validated and/or atlocation “b” in the above examples), similar to what is shown in theexample of FIG. 5 . NW may transmit a signaling including a TA (e.g. anabsolute TA value or a relative TA value) to the UE. In response to thereception of the TA, the UE could update its maintained TA based on theobtained TA. After the TA is obtained, the UE may validate themaintained TA from time to time, e.g. every once in a while. If thevalidation is passed, the maintained TA is considered as valid. If thevalidation is failed, the maintained TA could be considered as invalid.

The measurement result may at least include beam measurement result(s),cell measurement result(s), and/or one or more specific measurementresult(s) derived from one or more beam measurement result(s). Thespecific measurement result may also include cell measurement result,wherein the cell measurement result may be derived from one or more beammeasurement result(s).

The difference of measurement result at the first particular timing andmeasurement result at the second particular timing, e.g. between themeasurement result when the TA was obtained and the measurement resultwhen TA is validated, or between the measurement result when the TA isvalidated and the measurement result when last TA validation, may becompared with one or multiple (configured) threshold(s). If thecomparison is passed (e.g. the difference is not over the threshold), itmay mean that the TA is considered as valid, e.g. for the cell(s) orbeam(s) associated with the measurement result(s). Alternatively, it maymean that the TA is considered as valid for the corresponding beam(s).For the beam without valid TA, PUR transmission via the beam should beprohibited.

Beam measurement result may be with respect to a specific beam, e.g.measurement result of beam 1 in the above examples, measurement resultof the best beam (e.g. the beam with best radio condition). Beammeasurement result may be considered as a condition (to select beam or)as the measurement result for TA validation. For example, a beammeasurement result of a specific beam is derived from measuring SS/PBCHblock (SSB) or Channel State Information-Reference Signal (CSI-RS) onthe specific beam or associated with the specific beam.

Beam measurement result of a specific beam may be used for the TAvalidation (for PUR or D-PUR) on the specific beam. In one example, themeasurement results of the same beam at a first particular timing and ata second particular timing are compared, e.g. when TA was obtained andwhen TA is validated, or when TA is validated and last TA validation.More specifically, the difference between the beam measurement result ofthe specific beam at the first particular timing, e.g. when the TA wasobtained or last TA validation, and the beam measurement result of thesame specific beam at the second particular timing, e.g. when the TA isvalidated, could be used for the TA validation (for PUR or D-PUR) on thespecific beam. The difference could be compared with the threshold(s).If the comparison is passed (e.g. the difference is not over thethreshold(s)), the TA could be considered as valid on the specific beam,and PUR transmission on the specific beam may not be prohibited due toinvalid TA. Then, the UE may perform a PUR transmission on the specificbeam. If the comparison is failed (e.g. the difference is over thethreshold(s)), the TA could be considered as not valid on the specificbeam, and PUR transmission on the specific beam may be prohibited due toinvalid TA. TA validation on different beam may be evaluated separately.

Taking FIG. 6 as an example, the beam measurement result of beam 4 atthe first particular timing (e.g. when TA is obtained or last TAvalidation) is RSRP1_beam4 and the beam measurement result of beam 4 atthe second particular timing (e.g. when TA is validated) is RSRP2_beam4,if RSRP2_beam4−RSRP1_beam4<threshold, TA for PUR on beam 4 is consideredas valid. The beam measurement result of beam 1 at the first particulartiming (e.g. when TA is obtained or last TA validation) is RSRP1_beam1and the beam measurement result of beam 1 at the second particulartiming (e.g. when TA is validated) is RSRP2_beam1. IfRSRP2_beam1−RSRP1_beam1>threshold, TA for PUR on beam 1 is considered asnot valid.

Another example is shown in FIG. 8 (same UE movement as FIG. 7 ). Inthis example, the beam measurement result of beam 4 at the firstparticular timing (e.g. when TA is obtained or last TA validation) isRSRP1_beam4 and the beam measurement result of beam 4 at the secondparticular timing (e.g. when TA is validated) is RSRP2_beam4. IfRSRP2_beam4−RSRP1_beam4<threshold, TA for PUR on beam 4 is considered asvalid. The beam measurement result of beam 1 at the first particulartiming (e.g. when TA is obtained or last TA validation) is RSRP1_beam1and the beam measurement result of beam 1 at the second particulartiming (e.g. when TA is validated) is RSRP2_beam1. IfRSRP2_beam1−RSRP1_beam1>threshold, TA for PUR on beam 1 is considered asnot valid.

The specific measurement result (e.g. cell measurement result) may bederived from one or more beam measurement results.

The (set of) beam(s) to be considered to derive the beam measurementresult and/or the specific measurement result at the first particulartiming, e.g. when TA is obtained or last TA validation (e.g. cellmeasurement result at the first particular timing, denoted asRSRP1_cell), may include one or multiple of the following conditions:

-   -   The beam(s) used for scheduling the signaling including the        TA—NW may transmit a downlink control signaling (e.g. DCI) on a        downlink control channel (e.g. PDCCH) to schedule a downlink        transmission (e.g. on Physical Downlink Shared Channel (PDSCH))        to the UE. The downlink transmission may be a signaling        including the TA. If the NW transmits the downlink control        signaling via a specific beam, the UE may use the measurement        result of the specific beam (or derived from the specific beam)        as the measurement result at the first particular timing, e.g.        when TA is obtained or last TA validation, for TA validation.    -   The beam(s) used for transmitting the signaling including the        TA—NW may provide the TA to the UE via a downlink transmission        (e.g. on PDSCH). The downlink transmission may be a signaling        including the TA. If the NW transmits the signaling including        the TA via a specific beam, the UE may use the measurement        result of the specific beam (or derived from the specific beam)        as the measurement result at the first particular timing, e.g.        when TA is obtained or last TA validation, for TA validation.    -   The beam(s) indicated by network—NW may indicate the beam(s) to        be considered (to derive measurement result(s)) for TA        validation either explicitly or implicitly. For example, NW may        provide an explicit indication (or configuration) indicating the        beam(s) (to derive measurement result(s)) to be considered for        TA validation. For example, the UE may derive the beam(s) (to        derive measurement result(s)) to be considered for TA validation        based on some configuration provided by NW. For example, the UE        may derive the beam(s) (to derive measurement result(s)) to be        considered for TA validation based on some predefined rule(s).    -   The beam(s) configured with PUR—TA validation for PUR is used to        check whether PUR transmission is allowed. PUR configuration may        be beam specific. PUR may be configured in some beam(s) of the        cell and not in some other beam(s) of the cell. The beam(s)        configured with PUR may be considered (to derive measurement        result(s)) for TA validation. The beam(s) not configured with        PUR may not be considered (to derive measurement result(s)) for        TA validation.    -   The beam(s) with the best radio condition—The best beam (or the        beam with the best radio condition) may be the beam with highest        measurement quality (among the beams of the cell). The beam(s)        with the best radio condition may be limited to a specific        number, e.g. up to N beams. The specific number may be        predefined or configured by network. The specific number may        be 1. The specific number may be the same or separate from the        parameters used for cell reselection (e.g. the number for cell        reselection could be different from the number for TA        validation).        The beam(s) not configured with PUR may not be considered, e.g.        the beam(s) with the best radio condition among beam(s)        configured with PUR is considered.    -   The beam(s) with radio condition above a (second) threshold—The        threshold may be used for filtering qualified beams and may be        separate from the threshold used to compare with the difference        of the measurement results for TA validation. The threshold may        be configured by network. The threshold may be the same or        separate from the parameters used for cell reselection (e.g. the        threshold for cell reselection could be different from the        threshold for TA validation). The beam(s) with radio condition        above a threshold may be limited to a specific number, e.g. up        to N beams. The specific number may be predefined or configured        by network. The specific number may be 1. The specific number        may be separate from the parameters used for cell reselection        (e.g. the number for cell reselection could be different from        the number for TA validation).    -   Every beam of the cell—A cell may comprise multiple beams to        cover all directions of the cell. The measurement result of all        beams of the cell may be considered for TA validation. The beam        may be detected (or detectable) by the UE. The beam may be        common for all UEs in the cell.    -   Average of up to N beams above a threshold—The measurement        result may be derived from the linear average of the power        values of up to N highest beam measurement quantity values above        a configured threshold.

Alternatively or additionally, the beam(s) to be considered to derivethe specific measurement result may be the combination of the aboveitems, e.g. the beam(s) with best radio condition up to N beams andabove a (second) threshold, the beam(s) with best radio condition andconfigured with PUR, the beam(s) indicated by network and with radiocondition above a (second) threshold, and so on. The combination maymean that the beam(s) to be considered fulfills a combination of theabove conditions, e.g. the beam(s) fulfilling condition A+B. Thecombination may mean that the beam(s) to be considered include the beamfulfills one condition and the beam fulfills another condition, e.g. thebeam(s) fulfilling condition A+the beam(s) fulfilling condition B.

Other than the beam(s) to be considered, the rest of the beams of thecell may not be taken into account.

The (set of) beam(s) to be considered to derive the beam measurementresult and/or the specific measurement result at the second particulartiming, e.g. when TA is validated (e.g. cell measurement result at thesecond particular timing, denoted as RSRP2_cell), may include one ormultiple of the following conditions:

-   -   Same (set of) beam(s) which are considered at the first        particular timing (e.g. when TA is obtained or last TA        validation)—At the first particular timing, a (set of) beam(s)        is considered for TA validation (e.g. based on the above        alternatives). At the second particular timing, the same (set        of) beam(s) is considered for TA validation. Taking FIG. 6 as an        example, the measurement result at the first particular timing        (e.g. RSRP1), e.g. when TA is obtained or last TA validation (at        location “a”), is derived from beam measurement results of beam        1 and beam 2. At the second particular timing, e.g. when the UE        is in location “b” to validate TA, the measurement result (e.g.        RSRP2) is derived from beam measurement results of beam 1 and        beam 2 (at location “b”)    -   The beam(s) selected to be used for (potential) PUR        transmission—TA validation is used for PUR transmission. At the        second particular timing, e.g. when TA is validated, the UE        determines the beam(s) to be used for PUR transmission, assuming        that PUR transmission is allowed. For example, the determination        may be based on configuration of PUR and/or the radio condition        of beams. The UE uses the determined beam(s) to derive the        measurement result for TA validation. If the TA validation is        passed, the UE is allowed to perform PUR transmission via the        determined beam(s). Then the UE may select a beam among the        determined beam(s) for actual PUR transmission.    -   The beam(s) indicated by network—NW may indicate the beam(s) to        be considered (to derive measurement result(s)) for TA        validation either explicitly or implicitly. For example, NW may        provide an explicit indication (or configuration) indicating the        beam(s) (to derive measurement result(s)) to be considered for        TA validation. For example, the UE may derive the beam(s) (to        derive measurement result(s)) to be considered for TA validation        based on some configuration provided by NW. For example, the UE        may derive the beam(s) (to derive measurement result(s)) to be        considered for TA validation based on some predefined rule(s).    -   The beam(s) configured with PUR—TA validation for PUR is used to        check whether PUR transmission is allowed. PUR configuration may        be beam specific. PUR may be configured in some beam(s) of the        cell and not in some other beam(s) of the cell. The beam(s)        configured with PUR may be considered (to derive measurement        result(s)) for TA validation. The beam(s) not configured with        PUR may not be considered (to derive measurement result(s)) for        TA validation.    -   The beam(s) with best radio condition—The best beam (or the beam        with the best radio condition) may be the beam with highest        measurement quality (among the beams of the cell). The beam(s)        with the best radio condition may be limited to a specific        number, e.g. up to N beams. The specific number may be        predefined or configured by network. The specific number may        be 1. The specific number may be separate from the parameters        used for cell reselection (e.g. the number for cell reselection        could be different from the number for TA validation). The        beam(s) not configured with PUR may not be considered, e.g. the        beam(s) with the best radio condition among beam(s) configured        with PUR is considered.    -   The beam(s) with radio condition above a (second) threshold—The        threshold may be used for filtering qualified beams and may be        separate from the threshold used to compare with the difference        of the measurement results for TA validation. The threshold may        be configured by network. The threshold may be the same or        separate from the parameters used for cell reselection (e.g. the        threshold for cell reselection could be different from the        threshold for TA validation). The beam(s) with radio condition        above a threshold may be limited to a specific number, e.g. up        to N beams. The specific number may be predefined or configured        by network. The specific number may be 1. The specific number        may be separate from the parameters used for cell reselection        (e.g. the number for cell reselection could be different from        the number for TA validation).    -   Every beam of the cell—A cell may comprise multiple beams to        cover all directions of the cell. The measurement result of all        beams of the cell may be considered for TA validation. The beam        may be detected (or detectable) by the UE. The beam may be        common for all UEs in the cell.    -   Average of up to N beams above a threshold—The measurement        result may be derived from the linear average of the power        values of up to N highest beam measurement quantity values above        a configured threshold.

Alternatively or additionally, the beam(s) to be considered to derivethe specific measurement result may be the combination of the aboveitems, e.g. the beam(s) with best radio condition up to N beams andabove a (second) threshold, the beam(s) with best radio condition andconfigured with PUR, the beam(s) indicated by network and with radiocondition above a (second) threshold, and so on. The combination maymean that the beam(s) to be considered fulfills a combination of theabove conditions, e.g. the beam(s) fulfilling condition A+B. Thecombination may mean that the beam(s) to be considered include the beamfulfills one condition and the beam fulfills another condition, e.g. thebeam(s) fulfilling condition A+the beam(s) fulfilling condition B.

Other than the beam(s) to be considered, the rest of the beams of thecell may not be taken into account.

The (set of) beam(s) to be considered to derive the beam measurementresult and/or the specific measurement result at the first particulartiming (e.g. when TA is obtained or last TA validation, RSRP1_cell) andat the second particular timing (e.g. when TA is validated, RSRP2_cell)may be different (set of) beams. For example, the beam used forscheduling (or transmitting) the signaling including the TA isconsidered at the first particular timing (e.g. when TA is obtained orlast TA validation). At the second particular timing (e.g. when TA isvalidated), beam measurement result of a specific beam is compared tothe specific measurement result derived from beam used for scheduling(or transmitting) the signaling including the TA (or the beammeasurement result of the beam used for scheduling (or transmitting) thesignaling including the TA). If the comparison is passed (e.g. thedifference is not over the threshold), the TA is considered as valid onthe specific beam. PUR transmission on the specific beam is notprohibited. If the comparison is failed (e.g. the difference is over thethreshold), the TA is considered as not valid on the specific beam. PURtransmission on the specific beam is prohibited. TA validation ondifferent beam is evaluated separately.

An example is shown in FIG. 9 (same UE movement as FIG. 7 ). In thisexample, the beam to be considered at the first particular timing (e.g.when TA is obtained or last TA validation) is beam 1, e.g. the bestbeam, the beam schedules the TA, the beam receives the TA, etc. The beammeasurement result of beam 1 at the first particular timing (e.g. whenTA is obtained or last TA validation) is RSRP1_beam1 and the beammeasurement result of beam 4 at the second particular timing (e.g. whenTA is validated) is RSRP2_beam4. If RSRP2_beam4−RSRP1_beam1<threshold,TA for PUR on beam 4 is considered as valid. The beam measurement resultof beam 1 at the first particular timing (e.g. when TA is obtained orlast TA validation) is RSRP1_beam1 and the beam measurement result ofbeam 1 at the second particular timing (e.g. when TA is validated) isRSRP2_beam1. If RSRP2_beam1−RSRP1_beam1>threshold, TA for PUR on beam 1is considered as not valid.

The (set of) beam(s) to be considered to derive the beam measurementresult and/or the specific measurement result at the first particulartiming (e.g. when TA is obtained or last TA validation, RSRP1_cell) andat the second particular timing (e.g. when TA is validated, RSRP2_cell)may be the same (set of) beams. For example, the beam used fortransmitting the signaling including the TA is considered to derive themeasurement result at the first particular timing (e.g. when TA isobtained). At the second particular timing (e.g. when TA is validated),the measurement result of the same beam is used to compare with theprevious measurement result. If the comparison is passed, the TA of thecell is considered as valid. PUR transmission of the cell is notprohibited. If the comparison is failed, the TA of the cell isconsidered as invalid. PUR transmission of the cell is prohibited.

The (set of) beam(s) to be considered to derive the beam measurementresult and/or the specific measurement result at the first particulartiming (e.g. when TA is obtained or last TA validation, RSRP1_cell) andat the second particular timing (e.g. when TA is validated, RSRP2_cell)may be the (set of) beam(s) which fulfills the same condition(s). Theactual selected beam(s) may be the same. The actual selected beam(s) maybe different. For example, the beam with the best radio condition isconsidered to derive the measurement result at the first particulartiming (e.g. when TA is obtained or last TA validation) and themeasurement result at the second particular timing (e.g. when TA isvalidated), although the beam with the best condition are different atthe first particular timing (e.g. when TA was obtained or last TAvalidation) and at the second particular timing (e.g. when TA isvalidated).

The (set of) beam(s) to be considered to derive the beam measurementresult and/or the specific measurement result at the first particulartiming (e.g. when TA is obtained or last TA validation, RSRP1_cell) andat the second particular timing (e.g. when TA is validated, RSRP2_cell)may be the (set of) beam(s) which fulfills different condition(s). Theactual selected beam(s) may be the same. The actual selected beam(s) maybe different.

Other than the (set of) beam(s) to be considered to derive the beammeasurement result and/or the specific measurement result, the rest ofbeam(s) may be not considered in the derivation of the beam measurementresult and/or the specific measurement result.

The UE may obtain the TA by receiving a signaling including a TAcommand, e.g. the UE obtains the TA by adjusting the maintained TA basedon the TA command. The signaling may be a TA command MAC CE. Thesignaling may be a random access response. The TA may be the latestreceived TA (or the last obtained TA). The TA may be the latest receivedTA (or the last obtained TA) before RRC state transition (e.g. fromconnected state to idle state, from connected state to inactive state).The TA may be the latest received TA (or the last obtained TA) in thecurrent RRC state (e.g. connected state, idle state, inactive state).The TA may not be considered as invalid during (or upon) statetransition (e.g. from connected state to idle state, from connectedstate to inactive state).

The measurement result at the first or the second particular timing(e.g. when TA is obtained or last TA validation, when TA is validated)may be obtained and/or measured by the UE around the first or the secondparticular timing (e.g. the time when the UE obtains the TA, the lasttime the UE validates the TA, the time when the UE validates the TA),e.g. within a small time period. The measurement result at the first orthe second particular timing (e.g. when TA is obtained or last TAvalidation, when TA is validated) may be the last measurement resultobtained and/or measured by the UE before the first or the secondparticular timing (e.g. when the UE obtains the TA or last TAvalidation, when the UE validates the TA).

The measurement result may at least include RSRP, RSRQ, RSSI, SINR, orthe combination of the above. Since different beam may have differentinterference, and it may result in insufficient Tx power to use PURsuccessfully, measurement other than RSRP may be considered. Taking FIG.5 as an example, RSRP 2 could be replaced by RSRQ 2, RSSI 2, or SINR 2.Similarly, RSRP 1 could be replaced by RSRQ 1, RSSI 1, SINR 1. And thedifference of the measurement result to be compared with thethreshold(s) could be RSRP2−RSRP1, RSRQ2−RSRQ1, RSSI2−RSSI1, orSINR2−SINR1. Combination of them could also be considered.

The UE performs measurement on the serving cell and/or beams of theserving cell. The UE obtains a measurement result (e.g. beam measurementresult) based on the measurement. The UE obtains the measurement resultby lower layer. The measurement result may be further processed byhigher layer. For example, the measurement result may be filtered byhigher layers. For example, the measurement result may be the average ofthe previous measurement results (e.g. liner average, weighted average).

The measurement result derived from one or multiple beam measurementresults may be the average (e.g. linear average, weighted average) ofthe beam measurement results of each beam to be considered.

The beam measurement result may be the result of measuring a specificbeam of the cell. The cell measurement result may be the result ofmeasuring a specific cell, e.g. the serving cell. The cell measurementresult may be derived from the beam measurement result of one ormultiple beams of the cell.

The PUR may be dedicated and/or shared. The dedicated PUR may be D-PUR.The PUR may be provided by a dedicated signaling. The PUR may beprovided by system information.

The beam may be a NW beam. The beam may be associated to a SSB. The beammay be associated to a CSI-RS. The beam may be common in the cell. Thebeam may be UE specific.

The UE may be in the same serving cell at the first particular timing(e.g. when TA is obtained or last TA validation) and at the secondparticular timing (e.g. when TA is validated).

In one example, to validate TA with respect to a specific beam based onthe measurement result, the difference between the beam measurementresult of the specific beam at the first particular timing (e.g. when TAwas obtained or last TA validation) and the beam measurement result ofthe specific beam at the second particular timing (e.g. when TA isvalidated) is compared with one or multiple (configured) threshold(s).If the comparison is passed (e.g. the difference is not over thethreshold(s)), the TA with respect to the specific beam is considered asvalid. PUR transmission via the beam with valid TA may be allowed. Ifthe comparison is failed (e.g. the difference is over the threshold(s)),the TA with respect to the specific beam is considered as invalid. PURtransmission via the beam with invalid TA may be prohibited (due toinvalid TA).

In another example, to validate TA with respect to the (serving) cellbased on measurement result(s), beam measurement result(s) and/or thespecific measurement result (e.g. cell measurement result) may be takeninto account. For example, the comparison of the measurement results mayinclude: {(a): RSRP 2_beam 1−RSRP 1_beam 1, (b): RSRP 2_beam 2−RSRP 1beam 1, (c): RSRP 2_beam 3−RSRP 1_beam3, (d): RSRP 2_cell−RSRP 1_cell}.The validated TA may be considered as not valid in the followingalternatives:

Option 1: Comparison of any Beam is Failed

For example, if either (a), (b), or (c) is failed (e.g. over thethreshold(s)), TA of the cell is considered as invalid. Otherwise, TA ofthe cell is considered as valid.

Option 2: Comparison of N Beams are Failed

For example, if N=2, and any 2 results among (a)(b)(c) are failed (e.g.over the threshold(s)) (e.g. (b) and (c)), TA of the cell is consideredas invalid. Otherwise, TA of the cell is considered as valid.

Option 3: Comparison of all Beams are Failed

For example, if (a)(b)(c) are all failed (e.g. over the threshold(s)),TA of the cell is considered as invalid. Otherwise, TA of the cell isconsidered as valid.

Option 4: Comparison of the Specific Measurement Result (e.g. CellMeasurement Result) is Failed

For example, if (d) is failed (e.g. over the threshold(s)), TA of thecell is considered as invalid. Otherwise, TA of the cell is consideredas valid.

Option 5: Comparison of Both the Specific Measurement Result (e.g. CellMeasurement Result) and Beam Measurement Result are Failed

The comparison of the specific measurement result may be like option 4,and the comparison of beam measurement result may be any of option1/2/3. For example, considering option 3+4, if (a)(b)(c) and (d) are allfailed (e.g. over the threshold(s)), TA of the cell is considered asinvalid. Otherwise, TA of the cell is considered as valid.

The threshold(s) for beam measurement result comparison may be separatefrom the threshold(s) for the specific measurement result comparison.For example, TA validation considers the difference of the cellmeasurement result at the first particular timing and at the secondparticular timing as well as the difference of the beam measurementresult at the first particular timing and at the second particulartiming. To validate the TA, the difference of the cell measurementresult is compared to a first threshold (e.g. threshold_cell), and thedifference of the beam measurement result is compared to a secondthreshold (e.g. threshold_beam). Considering option 5, if both thecomparisons of cell and beam are passed, TA is considered as valid.

For example, a UE could receive a first signaling (e.g. RRCReleasemessage) to configure a preconfigured uplink resource (PUR) to be usedin a cell (e.g. when the UE is RRC_CONNECTED). Before the UE use the PURin the cell (e.g. when the UE is in RRC_INACTIVE), the UE needs todetermine whether a timing advance (e.g. to adjust a transmission timingof an UL transmission using the PUR) is valid or not. If the timingadvance is not valid, the UE cannot use the PUR. Otherwise, the UE maybe allowed to use the PUR (e.g. also based on other criteria).

Whether the timing advance is valid or not could be at least based on adifference between a first measurement result and a second measurementresult. The difference could be compared with one or more thresholds todetermine whether the timing advance is valid or not.

The first measurement result and the second measurement result could beRSRP. The first measurement result could be derived before deriving thesecond measurement result. Alternatively, the first measurement resultcould be derived after deriving the second measurement result.

The first measurement result may not be a cell measurement quantity ofthe cell. The first measurement result could be derived from beam(s) ofthe cell which is allowed to use the PUR. The first measurement resultmay not be derived from beam(s) of the cell which is not allowed to usethe PUR. The first measurement result could be derived from a firstnumber of beams of the cell. The first number could be more than one.Alternatively, the first number could be one.

The first measurement result could be a beam measurement quantity. Thefirst measurement result could be derived from a (single) beam, of thecell, where to receive a second signaling (e.g. timing advance command)to adjust the timing advance. Alternatively, the first measurementresult could be derived from a (single) beam, of the cell, where toreceive a third signaling (e.g. PDCCH) to schedule the second signaling.Alternatively, the first measurement result could be derived from a(single) beam, of the cell, with best radio condition, e.g. when the UEreceives the second signaling, when the UE receives the third signaling,when the UE determines whether to use the PUR, or when the UE determineswhether the timing advance is valid. Alternatively, the firstmeasurement result could be derived from a (single) beam, of the cell,with a radio condition (e.g. with respect to RSRP) above (or equal to) athreshold, e.g. when the UE receives the second signaling, when the UEreceives the third signaling, when the UE determines whether to use thePUR, or when the UE determines whether the timing advance is valid.

The first measurement result could be derived when the UE obtains thetiming advance (e.g. when the UE receives the second signaling or thethird signaling). Alternatively, the first measurement result could bederived when the UE receives an RRCRelease message (e.g. the firstsignaling) or performs a procedure for transiting (RRC) state fromRRC_CONNECTED to RRC_INACTIVE. Alternatively, the first measurementresult could be derived when the UE determines whether to use the PUR.Alternatively, the first measurement result could be derived when the UEdetermines whether the timing advance is valid.

The second measurement result could be a cell measurement quantity ofthe cell. Alternatively, the second measurement result may not be a cellmeasurement quantity of the cell. The second measurement result could bederived from beam(s) of the cell which is allowed to use the PUR. Thesecond measurement result may not be derived from beam(s) of the cellwhich is not allowed to use the PUR. The second measurement result couldbe derived from a second number of beams of the cell. The second numbercould be more than one. Alternatively, the second number could be one.

The second measurement result could be a beam measurement quantity. Thesecond measurement result could be derived from a (single) beam, of thecell, where to receive a second signaling (e.g. timing advance command)to adjust the timing advance. Alternatively, the second measurementresult could be derived from a (single) beam, of the cell, where toreceive a third signaling (e.g. PDCCH) to schedule the second signaling.Alternatively, the second measurement result could be derived from a(single) beam, of the cell, with best radio condition, e.g. when the UEreceives the second signaling, when the UE receives the third signaling,when the UE determines whether to use the PUR, or when the UE determineswhether the timing advance is valid. Alternatively, the secondmeasurement result could be derived from a (single) beam, of the cell,with a radio condition (e.g. with respect to RSRP) above (or equal to) athreshold, e.g. when the UE receives the second signaling, when the UEreceives the third signaling, when the UE determines whether to use thePUR, or when the UE determines whether the timing advance is valid.

The second measurement result could be derived when the UE obtains thetiming advance (e.g. when the UE receives the second signaling or thethird signaling). Alternatively, the second measurement result could bederived when the UE receives an RRCRelease message (e.g. the firstsignaling) or performs a procedure for transiting (RRC) state fromRRC_CONNECTED to RRC_INACTIVE. Alternatively, the second measurementresult could be derived when the UE determines whether to use the PUR.Alternatively, the second measurement result could be derived when theUE determines whether the timing advance is valid.

The first measurement result and the second measurement result could bederived from different beams of the cell. The first number and thesecond number could be different. Alternatively, the first measurementresult and the second measurement result could be derived from the samebeam(s) of the cell. The first number and the second number could be thesame.

The cell measurement quantity could be derived based on a linear averageof the power values of up to a number of highest beam measurementquantity values above a second threshold. The cell measurement quantitycould be used by the UE to determine whether to select another cell tocamp on (e.g. for cell reselection). The cell measurement quantity couldrepresent radio quality of a cell. The cell measurement quantity couldbe included in a measurement report as a cell quality.

The beam measurement quantity could be derived based on a power value ofone beam. The beam measurement quantity and the cell measurementquantity could be derived based on different formula. The beammeasurement quantity and the cell measurement quantity could be derivedfrom power values of different numbers of beams.

The cell could comprise a plurality of beams. A beam of the cell couldbe represented by a signal (e.g. SSB or CSI-RS) transmitted by a basestation controlling the cell.

In the method mentioned above, TA validation for PUR in NR multi-beamcell could be performed more accurately.

FIG. 10 is a flow chart 1000 according to one exemplary embodiment fromthe perspective of a UE. In step 1005, the UE receives a first signalingto configure a preconfigured uplink resource (PUR) to be used in a cell.In step 1010, the UE determines whether to use the PUR in the cell atleast based on whether a timing advance is valid, wherein whether thetiming advance is valid is based on a difference between a firstmeasurement result and a second measurement result, and wherein thefirst measurement result is not a cell measurement quantity of the cell.

In one embodiment, the first measurement result could be derived at afirst timing and the second measurement result is derived at a secondtiming. The first timing or the second timing could be when the UEobtains the timing advance. Alternatively, the first timing or thesecond timing could be when the UE receives a RRCRelease message orperforms a procedure for transiting state from RRC_CONNECTED toRRC_INACTIVE. The first timing or the second timing could be when the UEdetermines whether to use the PUR.

In one embodiment, the first measurement result could be a first beammeasurement quantity. The second measurement result could be a secondbeam measurement quantity or the cell measurement quantity. The firstmeasurement result or the second measurement result could be derivedfrom a single beam, of the cell, where to receive a second signaling toadjust the timing advance or a third signaling to schedule the secondsignaling.

In one embodiment, the first measurement result or the secondmeasurement result could be derived from a single beam, of the cell,with best radio condition when the UE receives a second signaling toadjust the timing advance or a third signaling to schedule the secondsignaling. The first measurement result and the second measurementresult could be different beam measurement quantities derived fromdifferent beams of the cell.

Referring back to FIGS. 3 and 4 , in one exemplary embodiment of a UE.The UE 300 includes a program code 312 stored in the memory 310. The CPU308 could execute program code 312 to enable the UE (i) to receive afirst signaling to configure a preconfigured uplink resource (PUR) to beused in a cell, and (ii) to determine whether to use the PUR in the cellat least based on whether a timing advance is valid, wherein whether thetiming advance is valid is based on a difference between a firstmeasurement result and a second measurement result, and wherein thefirst measurement result is not a cell measurement quantity of the cell.Furthermore, the CPU 308 can execute the program code 312 to perform allof the above-described actions and steps or others described herein.

FIG. 11 is a flow chart 1100 according to one exemplary embodiment fromthe perspective of a UE. In step 1105, the UE obtains a firstmeasurement result derived from a first set of beams at a firstparticular timing. In step 1110, the UE obtains a second measurementresult derived from a second set of beams at a second particular timing.In step 1115, the UE validates the timing advance based on the firstmeasurement result and the second measurement result.

In one embodiment, the first or the second measurement result could bebeam measurement result. Alternatively, the first or the secondmeasurement result could be cell measurement result.

In one embodiment, the first or the second set of beams could be thebeam used for scheduling the downlink transmission including the timingadvance, e.g. the beam where PDCCH is transmitted. Alternatively, thefirst or the second set of beams could be the beam used for transmittingthe downlink transmission including the timing advance, e.g. the beamwhere PDSCH is transmitted. The first or the second set of beams couldbe indicated by network explicitly or implicitly. The first or thesecond set of beams could be configured with PUR.

In one embodiment, the first or the second set of beams could be withhighest measurement quality, and/or with measurement quality above asecond threshold. The first or the second set of beams could be limitedto a specific number, e.g. up to N beams. The first or the second set ofbeams could be every beam of the cell. The first or the second set ofbeams could be used for (potential) PUR transmission.

In one embodiment, the first set of beams and the second set of beamscould be the same. Alternatively, the first set of beams and the secondset of beams could be different.

In one embodiment, the UE could validate the timing advance with respectto a specific beam, or with respect to a serving cell. The UE could alsovalidate the timing advance by comparing the difference of the firstmeasurement result and the second measurement result to a firstthreshold.

In one embodiment, the validation could be passed (and/or the timingadvance is considered as valid) if the difference is not over the firstthreshold. On the other hand, the validation could be failed (and/or thetiming advance is considered as invalid) if the difference is over thefirst threshold.

In one embodiment, the first particular timing could be when the UEobtains a timing advance. The second particular timing could be when theUE validates the timing advance. The beam measurement result could bethe result of measuring a specific beam of the cell. The cellmeasurement result could be derived from one or multiple beammeasurement results.

Referring back to FIGS. 3 and 4 , in one exemplary embodiment of a UE.The UE 300 includes a program code 312 stored in the memory 310. The CPU308 could execute program code 312 to enable the UE (i) to obtain afirst measurement result derived from a first set of beams at a firstparticular timing, (ii) to obtain a second measurement result derivedfrom a second set of beams at a second particular timing, and (iii) tovalidate the timing advance based on the first measurement result andthe second measurement result. Furthermore, the CPU 308 can execute theprogram code 312 to perform all of the above-described actions and stepsor others described herein.

Various aspects of the disclosure have been described above. It shouldbe apparent that the teachings herein could be embodied in a widevariety of forms and that any specific structure, function, or bothbeing disclosed herein is merely representative. Based on the teachingsherein one skilled in the art should appreciate that an aspect disclosedherein could be implemented independently of any other aspects and thattwo or more of these aspects could be combined in various ways. Forexample, an apparatus could be implemented or a method could bepracticed using any number of the aspects set forth herein. In addition,such an apparatus could be implemented or such a method could bepracticed using other structure, functionality, or structure andfunctionality in addition to or other than one or more of the aspectsset forth herein. As an example of some of the above concepts, in someaspects concurrent channels could be established based on pulserepetition frequencies. In some aspects concurrent channels could beestablished based on pulse position or offsets. In some aspectsconcurrent channels could be established based on time hoppingsequences. In some aspects concurrent channels could be establishedbased on pulse repetition frequencies, pulse positions or offsets, andtime hopping sequences.

Those of skill in the art would understand that information and signalsmay be represented using any of a variety of different technologies andtechniques. For example, data, instructions, commands, information,signals, bits, symbols, and chips that may be referenced throughout theabove description may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orparticles, or any combination thereof.

Those of skill would further appreciate that the various illustrativelogical blocks, modules, processors, means, circuits, and algorithmsteps described in connection with the aspects disclosed herein may beimplemented as electronic hardware (e.g., a digital implementation, ananalog implementation, or a combination of the two, which may bedesigned using source coding or some other technique), various forms ofprogram or design code incorporating instructions (which may be referredto herein, for convenience, as “software” or a “software module”), orcombinations of both. To clearly illustrate this interchangeability ofhardware and software, various illustrative components, blocks, modules,circuits, and steps have been described above generally in terms oftheir functionality. Whether such functionality is implemented ashardware or software depends upon the particular application and designconstraints imposed on the overall system. Skilled artisans mayimplement the described functionality in varying ways for eachparticular application, but such implementation decisions should not beinterpreted as causing a departure from the scope of the presentdisclosure.

In addition, the various illustrative logical blocks, modules, andcircuits described in connection with the aspects disclosed herein maybe implemented within or performed by an integrated circuit (“IC”), anaccess terminal, or an access point. The IC may comprise a generalpurpose processor, a digital signal processor (DSP), an applicationspecific integrated circuit (ASIC), a field programmable gate array(FPGA) or other programmable logic device, discrete gate or transistorlogic, discrete hardware components, electrical components, opticalcomponents, mechanical components, or any combination thereof designedto perform the functions described herein, and may execute codes orinstructions that reside within the IC, outside of the IC, or both. Ageneral purpose processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices, e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or any other suchconfiguration.

It is understood that any specific order or hierarchy of steps in anydisclosed process is an example of a sample approach. Based upon designpreferences, it is understood that the specific order or hierarchy ofsteps in the processes may be rearranged while remaining within thescope of the present disclosure. The accompanying method claims presentelements of the various steps in a sample order, and are not meant to belimited to the specific order or hierarchy presented.

The steps of a method or algorithm described in connection with theaspects disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module (e.g., including executable instructions and relateddata) and other data may reside in a data memory such as RAM memory,flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a harddisk, a removable disk, a CD-ROM, or any other form of computer-readablestorage medium known in the art. A sample storage medium may be coupledto a machine such as, for example, a computer/processor (which may bereferred to herein, for convenience, as a “processor”) such theprocessor can read information (e.g., code) from and write informationto the storage medium. A sample storage medium may be integral to theprocessor. The processor and the storage medium may reside in an ASIC.The ASIC may reside in user equipment. In the alternative, the processorand the storage medium may reside as discrete components in userequipment. Moreover, in some aspects any suitable computer-programproduct may comprise a computer-readable medium comprising codesrelating to one or more of the aspects of the disclosure. In someaspects a computer program product may comprise packaging materials.

While the invention has been described in connection with variousaspects, it will be understood that the invention is capable of furthermodifications. This application is intended to cover any variations,uses or adaptation of the invention following, in general, theprinciples of the invention, and including such departures from thepresent disclosure as come within the known and customary practicewithin the art to which the invention pertains.

The invention claimed is:
 1. A method for a User Equipment (UE), comprising: receiving a first signaling to configure a preconfigured uplink resource (PUR) to be used in a cell; and determining whether to use the PUR in the cell at least based on whether a timing advance is valid, wherein whether the timing advance is valid is based on at least a difference between a first measurement result and a second measurement result derived by the UE, and wherein the second measurement result is derived from one or more beams of the cell with highest measurement quality among a plurality of beams of the cell.
 2. The method of claim 1, wherein the first measurement result is derived at a first timing and the second measurement result is derived at a second timing.
 3. The method of claim 2, wherein the first timing or the second timing is when the UE obtains the timing advance.
 4. The method of claim 2, wherein the first timing or the second timing is when the UE receives a RRCRelease message or performs a procedure for transiting state from RRC_CONNECTED to RRC_INACTIVE.
 5. The method of claim 2, wherein the first timing or the second timing is when the UE determines whether to use the PUR.
 6. The method of claim 1, wherein the first measurement result is derived from at most the number of beams of the cell with highest measurement quality.
 7. The method of claim 1, wherein measurement quality of each beam used to derive the second measurement result is above a threshold.
 8. The method of claim 1, wherein the first measurement result is derived from a single beam, of the cell, where to receive a second signaling to adjust the timing advance or a third signaling to schedule the second signaling.
 9. The method of claim 1, wherein the first measurement result or the second measurement result is derived from a single beam, of the cell, with highest measurement quality when the UE receives a second signaling to adjust the timing advance or a third signaling to schedule the second signaling.
 10. The method of claim 1, wherein the first measurement result and the second measurement result are derived from different beams of the cell.
 11. A User Equipment (UE), comprising: a processor; and a memory operatively coupled to the processor, wherein the processor is configured to execute a program code to: receive a first signaling to configure a preconfigured uplink resource (PUR) to be used in a cell; and determine whether to use the PUR in the cell at least based on whether a timing advance is valid, wherein whether the timing advance is valid is based on at least a difference between a first measurement result and a second measurement result derived by the UE, and wherein the second measurement result is derived from one or more beams of the cell with highest measurement quality among a plurality of beams of the cell.
 12. The UE of claim 11, wherein the first measurement result is derived at a first timing and the second measurement result is derived at a second timing.
 13. The UE of claim 12, wherein the first timing or the second timing is when the UE obtains the timing advance.
 14. The UE of claim 12, wherein the first timing or the second timing is when the UE receives a RRCRelease message or performs a procedure for transiting state from RRC_CONNECTED to RRC_INACTIVE.
 15. The UE of claim 12, wherein the first timing or the second timing is when the UE determines whether to use the PUR.
 16. The UE of claim 11, wherein the first measurement result is derived from at most the number of beams of the cell with highest measurement quality.
 17. The UE of claim 11, wherein measurement quality of each beam used to derive the second measurement result is above a threshold.
 18. The UE of claim 11, wherein the first measurement result is derived from a single beam, of the cell, where to receive a second signaling to adjust the timing advance or a third signaling to schedule the second signaling.
 19. The UE of claim 11, wherein the first measurement result or the second measurement result is derived from a single beam, of the cell, with highest measurement quality when the UE receives a second signaling to adjust the timing advance or a third signaling to schedule the second signaling.
 20. The UE of claim 11, wherein the first measurement result and the second measurement result are derived from different beams of the cell. 